| grim(adjective, determined, resolute, uncompromising, unshakeable) |
| hell-bent(adjective, fixed, persistent, obstinate, absorbed) |
| hidebound(adjective, determined, resolute, persistent, obstinate) |
| industrious(adjective, energetic, determined, active, vigorous) |
| intractable(adjective, tough, determined, unreasonable, fixed) |
| inveterate(adjective, certain, determined, usual, regular) |
| irremovable |
| long-lasting(adjective, stable, constant, enduring, lasting) |
| motionless(adjective, calm, secure, moving, still) |
| never-failing(adjective, strong, complete, flat, firm) |
| noble |
| perseverant |
| predictable(adjective, good, strong, honest, solid) |
| rooted(adjective, secure, certain, determined, usual) |
| severe(adjective, persistent, rigid, obstinate, insistent) |
| spunky(adjective, resolute, tenacious) |
| thorough(adjective, complete, total, definite, resolute) |
| uniform(adjective, calm, strong, secure, firm) |
| unmoving(adjective, move, calm, still, fixed) |
| unquestioning(adjective, set, clear, complete, warm) |